Made available in DSpace on 2014-12-17T15:48:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-02 / Multimedia systems must incorporate middleware concepts in order to abstract hardware and operational systems issues. Applications in those systems may be executed in different kinds of platforms, and their components need to communicate with each other. In this context, it is needed the definition of specific communication mechanisms for the transmission of information flow. This work presents a interconnection component model for distributed multimedia environments, and its implementation details. The model offers specific communication mechanisms for transmission of information flow between software components considering the Cosmos framework requirements in order to support component dynamic reconfiguration / Sistemas multim?dia devem incorporar conceitos de middleware de forma a abstrair especificidades de hardware e sistemas operacionais. Aplica??es nestes sistemas podem ser executadas em diferentes tipos de plataformas, e os componentes destes sistemas precisam interagir uns com os outros. Neste contexto, faz-se necess?rio a defini??o de mecanismos de comunica??o espec?ficos para a transmiss?o de fluxos de informa??o. Este trabalho apresenta um modelo para a interconex?o de componentes em ambientes multim?dia, e sua arquitetura de implementa??o. O modelo oferece mecanismos de comunica??o espec?ficos para a transmiss?o de fluxos de informa??o entre componentes de software atendendo aos requisitos do framework Cosmos de maneira a suportar a reconfigura??o din?mica de componentes

Made available in DSpace on 2014-12-17T15:48:13Z (GMT). No. of bitstreams: 1 CarlosES.pdf: 1065336 bytes, checksum: c1840ccdd384fc7c59635d8e173e484f (MD5) Previous issue date: 2007-02-05 / Multimedia systems must incorporate middleware concepts in order to abstract hardware and operational systems issues. Applications in those systems may be executed in different kinds of platforms, and their components need to communicate with each other. In this context, it is needed the definition of specific communication mechanisms for the transmission of information flow. This work presents a interconnection component model for distributed multimedia environments, and its implementation details. The model offers specific communication mechanisms for transmission of information flow between software components considering the Cosmos framework requirements in order to support component dynamic reconfiguration / Sistemas multim?dia devem incorporar conceitos de middleware de forma a abstrair especificidades de hardware e sistemas operacionais. Aplica??es nestes sistemas podem ser executadas em diferentes tipos de plataformas, e os componentes destes sistemas precisam interagir uns com os outros. Neste contexto, faz-se necess?rio a defini??o de mecanismos de comunica??o espec?ficos para a transmiss?o de fluxos de informa??o. Este trabalho apresenta um modelo para a interconex?o de componentes em ambientes multim?dia, e sua arquitetura de implementa??o. O modelo oferece mecanismos de comunica??o espec?ficos para a transmiss?o de fluxos de informa??o entre componentes de software atendendo aos requisitos do framework Cosmos de maneira a suportar a reconfigura??o din?mica de componentes

Made available in DSpace on 2014-12-17T15:47:53Z (GMT). No. of bitstreams: 1 FelipeAPP_DISSERT.pdf: 2094888 bytes, checksum: 2f662bc70058d8584f0a23ab28517f43 (MD5) Previous issue date: 2011-01-19 / Distributed multimedia systems have highly variable characteristics, resulting in new requirements while new technologies become available or in the need for adequacy in accordance with the amount of available resources. So, these systems should provide support for dynamic adaptations in order to adjust their structures and behaviors at runtime. This paper presents an approach to adaptation model-based and proposes a reflective and component-based framework for construction and support of self-adaptive distributed multimedia systems, providing many facilities for the development and evolution of such systems, such as dynamic adaptation. The propose is to keep one or more models to represent the system at runtime, so some external entity can perform an analysis of these models by identifying problems and trying to solve them. These models integrate the reflective meta-level, acting as a system self-representation. The framework defines a meta-model for description of self-adaptive distributed multimedia applications, which can represent components and their relationships, policies for QoS specification and adaptation actions. Additionally, this paper proposes an ADL and architecture for model-based adaptation. As a case study, this paper presents some scenarios to demonstrate the application of the framework in practice, with and without the use of ADL, as well as check some characteristics related to dynamic adaptation / Sistemas multim?dia distribu?dos possuem caracter?sticas bastante vari?veis, podendo implicar em novos requisitos ? medida que novas tecnologias s?o disponibilizadas ou na necessidade de adequa??o de acordo com a quantidade de recursos dispon?veis. Dessa forma, tais aplica??es devem ser capazes de realizar ajustes e adapta??es din?micas, permitindo alterar sua estrutura e comportamento. Com o objetivo de prover capacidades de autoadapta??o nesses sistemas, este trabalho apresenta uma abordagem de adapta??o baseada em modelos. ? proposto um framework reflexivo e baseado em componentes para a constru??o e suporte de sistemas multim?dia distribu?dos autoadaptativos, fornecendo v?rias facilidades para o desenvolvimento e evolu??o de tais sistemas, como adapta??o din?mica. A proposta do framework ? manter um ou mais modelos de representa??o do sistema em tempo de execu??o, de modo que alguma entidade externa possa realizar uma an?lise desses modelos identificando problemas e tentando resolv?-los. Esses modelos integram o metan?vel reflexivo das aplica??es atuando como uma autorrepresenta??o do sistema. Para isso, o framework define um metamodelo para a descri??o de aplica??es multim?dia distribu?das autoadaptativas, o qual ? capaz de representar componentes e seus relacionamentos, pol?ticas para especifica??o de QoS e a??es de adapta??o. Adicionalmente, ? proposta uma ADL e uma arquitetura para adapta??o baseada em modelos. Como estudo de caso o trabalho apresenta alguns cen?rios buscando exemplificar o uso do framework na pr?tica, com e sem o uso da ADL, bem como verificar algumas caracter?sticas relacionadas ? adapta??o din?mica